• Journal of Integrative Natural Science
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• v.9 no.3
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• pp.171-176
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• 2016

Rap1 is a key regulator of cell adhesion and migration. Although increasing evidence indicates that the Rap1 signaling pathway is involved in the process of bone remodeling, the mechanism by which Rap1 regulates osteoblastic differentiation and cell adhesion remains unknown. Here, we investigated the morphological characteristics and osteoblastic differentiation of cells expressing constitutively activated form of Rap1A (Rap1ACA) or Rap1 GTPase activating protein Rap1GAP and found that activated Rap1 induces osteoblastic differentiation and cell adhesion as well as cell spreading. When osteoblastic differentiation was induced, Rap1ACA cells showed considerably higher levels of calcium deposits than the wild-type and Rap1GAP-overexpressing cells did. Rap1ACA cells showed increased spreading and size, as well as strong cell adhesion and significantly decreased growth rates. F-actin staining using phalloidin revealed several thin thread-like filopodia around the protrusions in Rap1ACA cells, which possibly contribute to the increased cell adhesion.

• Parasites, Hosts and Diseases
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• v.60 no.6
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• pp.393-400
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• 2022

Human infection with simian malaria Plasmodium knowlesi is a cause for concern in Southeast Asian countries, especially in Malaysia. A previous study on Peninsular Malaysia P. knowlesi rhoptry associated protein-1 (PkRAP1) gene has discovered the existence of dimorphism. In this study, genetic analysis of PkRAP1 in a larger number of P. knowlesi samples from Malaysian Borneo was conducted. The PkRAP1 of these P. knowlesi isolates was PCR-amplified and sequenced. The newly obtained PkRAP1 gene sequences (n=34) were combined with those from the previous study (n=26) and analysed for polymorphism and natural selection. Sequence analysis revealed a higher genetic diversity of PkRAP1 compared to the previous study. Exon II of the gene had higher diversity (π=0.0172) than exon I (π=0.0128). The diversity of the total coding region (π=0.0167) was much higher than those of RAP1 orthologues such as PfRAP-1 (π=0.0041) and PvRAP1 (π=0.00088). Z-test results indicated that the gene was under purifying selection. Phylogenetic tree and haplotype network showed distinct clustering of Peninsular Malaysia and Malaysian Borneo PkRAP1 haplotypes. This geographical-based clustering of PkRAP1 haplotypes provides further evidence of the dimorphism of the gene and possible existence of 2 distinct P. knowlesi lineages in Malaysia.

• Journal of the Korean Geotechnical Society
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• v.20 no.5
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• pp.127-134
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• 2004

Rammed Aggregate Pier (RAP) has extensive applicability as for a foundation of structures. In this study, bearing capacity of the reinforced ground by RAP and the failure behavior of RAP are investigated through experiments. RAPs with diameters of 45, 60, 70 mm were installed in sand, of which relative densities are 60, 70, 90%. Then, two columns of pressure gauges, near the RAPs and one diameter off from the center of piers, are installed 5, 10, 15, 20, 25, 30 cm from the surface of the ground. The test results show that maximum lateral earth pressure is observed near 5∼10 cm (1.0∼2.0D) from the surface, which indicates the occurrence of bulging failure type. In addition, deformation of RAP in radial direction increases with lower relative density of the ground. Furthermore, lateral stress distribution decreases with depth.

• BMB Reports
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• v.52 no.9
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• pp.572-576
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• 2019

Bisphosphonates are the mainstay of therapy worldwide for osteoporosis. However, bisphosphonates also have limitations. The objective of this study was to determine the role of miR-101-3p/Rap1b signal pathway in osteoclast differentiation after treatment with bisphosphonates. Our results revealed that miR-101-3p was an important regulator in bisphosphonates treated-osteoclasts. When miR-101-3p was down-regulated in bone marrow-derived macrophage-like cells (BMMs), the development of mature osteoclasts was promoted, and vice versa. However, alendronate decreased multinucleated cell number regardless of whether miR-101-3p was knocked down or over-expressed. TRAP activity assay confirmed the above results. Luciferase assay indicated that miR-101-3p was a negative regulator of Rap1b. Western blot analysis revealed that protein expression level of Rap1b in BMMs transfected with OV-miR-101-3p was lower than that in BMMs transfected with an empty vector. Rap1b overexpression increased TRAP-positive multinucleated cells, while Rap1b inhibition decreased the cell numbers. In vivo data showed that miR-101-3p inhibited osteoclast differentiation in ovariectomized mice while overexpressed of Rap1b blocked the differentiation. Taken together, our data demonstrate that miR-101-3p/Rap1b signal pathway plays a key role in osteoclast differentiation after treatment with bisphosphonates.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.337-341
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• 2001

To isolate antifungal substances from Korean radish (Raphanus Sativus L.) seeds, various purification techniques such as DE52 cellulose anion exchange, SP-Sephadex C-25 cation exchange, and Sephadex G-50 gel filtration chromatographies were used. The molecular masses of two purified R. sativus antifungal proteins (RAPs) were estimated to be about 6.1 kDa (RAP-1) and 6.2 kDa (RAP-2) by SDS-PAGE, and 5.8 kDa(RAP-1) and 6.2 kDa (RAP-2 by a gel filtration chromatography, respectively. Purified proteins RAP-1 and 2 clearly exhibited different growth inhibitory activities against other microorganisms like Candida albicans and Saccharomyces cerevisiae. Although they have similar molecular masses, both RAP-1 and 2 proteins are not identical because their microbial inhibitory actions were different. Therefore, RAP-1 could be a new antifungal protein when compared with the antifungal activities of 2S albumins, Rs-AFPs, Mj-AMPs, chitinase, glucanase, permatin, and ribosome inactivating proteins, all of which are anifungal proteins of plants.

• Structural Engineering and Mechanics
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• v.67 no.3
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• pp.283-290
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• 2018

This paper presents the results of a study that investigated the influence of using recycled coarse aggregate (RCA) and recycled asphalt pavement (RAP) on the properties of pervious concrete (PC). The natural aggregate (NA) was replaced by RCA and RAP in the PC with replacement levels of 0%, 20%, 40%, 60% and 80% by the total weight of NA, respectively. In addition to incorporating RAP and RCA in the same mixes with replacement levels of: (1) 20% RAP and 80% RCA; (2) 60% RAP and 40% RCA; and (3) 80% RAP and 20% RCA. Water permeability, thermal conductivity, density, porosity, void content, and compressive, splitting tensile and flexural strengths were studied in this paper. The results showed that using RCA, RAP, and (RAP-RCA) enhanced the properties of PC in general and improved the mechanical properties significantly in particular. The optimum mix was reported to be the 60% RAP and 40% RCA. Accordingly, the RAP has the potential to be used in PC in order to reduce the negative impact of RAP on the human health and environment.

• International Journal of Highway Engineering
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• v.19 no.1
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• pp.37-44
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• 2017

PURPOSES : This study is primarily focused on evaluating the effects of the non-linear stress-strain behavior of RAP concrete on structural response characteristics as is applicable to concrete pavement. METHODS : A 3D FE model was developed by incorporating the actual stress-strain behavior of RAP concrete obtained via flexural strength testing as a material property model to evaluate the effects of the non-linear stress-strain behavior to failure on the maximum stresses in the concrete slab and potential performance prediction results. In addition, a typical linear elastic model was employed to analyze the structural responses for comparison purposes. The analytical results from the FE model incorporating the actual stress-strain behavior of RAP concrete were compared to the corresponding results from the linear elastic FE model. RESULTS : The results indicate that the linear elastic model tends to yield higher predicted maximum stresses in the concrete as compared to those obtained via the actual stress-strain model. Consequently, these higher predicted stresses lead to a difference in potential performance of the concrete pavement containing RAP. CONCLUSIONS : Analysis of the concrete pavement containing RAP demonstrated that an appropriate analytical model using the actual stress-strain characteristics should be employed to calculate the structural responses of RAP concrete pavement instead of simply assuming the concrete to be a linear elastic material.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.5 no.2
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• pp.166-173
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• 2002

Purpose: Recurrent abdominal pain (RAP) is common, affecting between 7% and 25% of school-aged children and young adult. This study was designed to assess the relationship between RAP and depressive trends in school-aged children. Methods: In 1999, We surveyed 1,181 elementary school children (566 boys and 615 girls) whose ages ranged from 9 to 12 years. The degree of depression was compared between the group with RAP and normal control group without RAP according to Korean Children's Depression Inventory (CDI) of Kovacs and Beck. Results: The number of the group with RAP was significantly higher in female (25.7%) than in male (18.9%). The most common site of abdominal pain was periumbilical. The mean depression score in the group with RAP was higher than that of the control group. The depression score was significantly higher in the group with RAP who has frequently pain and additional symptoms. The depression score was significantly higher in the group with RAP who prefered to play alone, did not enjoy going to school and had few friends than in the group with RAP who had a lot of friends, had active and meticulous characters. The depression scores were not significantly different according to the duration of abdominal pain, the onset time of pain, and the day of pain in the group with RAP. Conclusion: The depression score of the group with RAP was higher than that of normal group. So, there is relatively a specific association between childhood RAP and depression in school aged children. It is good for physicians to consider psychological support in the treatment of childhood RAP.

• International Journal of Highway Engineering
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• v.20 no.1
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• pp.69-76
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• 2018

PURPOSES : This study determined the optimal usage rate of RAP (reclaimed asphalt pavement) using cold central-plant recycling (CCPR) on a road-surface layer. In addition, a mixture-aggregate gradation design and a curing method based on the proposed rate for the surface-layer mix design were proposed. METHODS : First, current research trends were investigated by analyzing the optimum moisture content, mix design, and quality standards for surface layers in Korea and abroad. To analyze the aggregate characteristics of the RAP, its aggregate-size characteristics were analyzed through the combustion asphalt content test and the aggregate sieve analysis test. Moreover, aggregate-segregation experiments were performed to examine the possibility of RAP aggregate segregation from field compaction and vehicle traffic. After confirming the RAP quality standards, coarse aggregate and fine aggregate, aggregate-gradation design and quality tests were conducted for mixtures with 40% and 50% RAP usage. The optimum moisture content of the surface-layer mixture containing RAP was tested, as was the evapotranspiration effect on the surface-layer mixture of the optimum moisture content. RESULTS : After analyzing the RAP recycled aggregate size and extraction aggregate size, 13-8mm aggregate was found to be mostly 8mm aggregate after combustion. After using surface-chipping and mixing methods to examine the possibility of RAP aggregate segregation, it was found that the mixing method contributed very little for 3.32%, and because the surface-chipping method applied compaction energy directly as the maximum assumption the separation ratio was 15.46%. However, the composite aggregate gradation did not change. Using a 40% RAP aggregate rate on the surface-layer mixture for cold central-plant recycling satisfied the Abroad quality standard. The optimum moisture content of the surface-layer mixture was found to be 7.9% using the modified Marshall compaction test. It was found that the mixture was over 90% cured after curing at $60^{\circ}C$ for two days. CONCLUSIONS : To use the cold central-plant recycling mixture on a road-surface layer, a mixture-aggregate gradation design was proposed as the RAP recycled aggregate size without considering aggregate segregation, and the RAP optimal usage rate was 40%. In addition, the modified Marshall compaction test was used to determine the optimum moisture content as a mix-design parameter, and the curing method was adapted using the method recommended by Asphalt Recycling & Reclaiming Association (ARRA).

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.21-30
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• 2015

PURPOSES : The purpose of this study was to evaluate the performance of rapid-setting polymer-modified asphalt mixtures with a high reclaimed asphalt pavement (RAP) content. METHODS: A literature review revealed that emulsified asphalt is actively used for cold-recycled pavement. First, two types of rapid-setting polymer-modified asphalt emulsion were prepared for application to high-RAP material with no virgin material content. The quick-setting polymer-modified asphalt mixtures using two types of rapid-setting polymer-modified asphalt emulsion were subjected to the following tests: 1) Marshall stability test, 2) water immersion stability test and 3) indirect tensile strength ratio test. RESULTS AND CONCLUSIONS : Additional re-calibration of the RAP was needed for laboratory verification because the results of analyzing RAP aggregates, which were collected from different job sites, did not deviate from the normal range. The Marshall stability of each type of binder under dry conditions was good. However, the Type B mixtures with bio-additives performed better in the water immersion stability test. Moreover, the overall results of the indirect tensile strength test of RAP mixtures with Type B emulsions exceeded 0.7. Further research, consisting of lab testing and on-site application, will be performed to verify the possibility of using RAP for minimizing the closing of roadways.